The invention concerns a method for passivating a silicon carbide (SiC) surface against oxygen.
A plurality of semiconductor structures based on silicon carbide (SiC) as the semiconductor material are known. In the manufacture of such SiC semiconductor structures, the surfaces of SiC single crystals, which in some cases are already preprocessed, must often be exposed to an oxygen-containing atmosphere, for example during interim storage of the SiC single crystal or transport from one process location to another. In an oxygen-containing atmosphere, however, a natural oxide coating consisting of SiO.sub.2 forms on the surface of the SiC single crystal. The thickness of this oxide coating after one week in air, for example, is already 2 nm. This natural oxide coating is generally undesirable, and must therefore be removed, by sputtering or with hydrofluoric acid (HF), before a subsequent process step.
It is known, from the publication Thin Solid Films 241 (1994), pp. 305-309, to treat silicon carbide surfaces with a hydrogen (H.sub.2) plasma and saturate the free bonds at the SiC surface by deposition of H.sub.2 ions. A general passivation is achieved thereby.